1. Field of the invention
This application is the National Stage of International Application No. PCT/EP2009/055667, filed on May 11, 2009, which claimed the benefit of German Application No. DE 10 2008 023 750.7 filed May 15, 2008, which are hereby both incorporated by reference. The International Application No. PCT/EP2009/055667 was published on Nov. 19, 2009.
The present invention concerns a driver protection system for a vehicle, in particular for a utility vehicle such as for example a fork lift truck, a tractor or a construction-site or agricultural machine.
2. State of the art
Various driver protection systems are known in commercial and utility vehicle such as fork lift trucks for protecting the driver from injury for example in the case of accidents caused by load or centrifugal force or tipping of the vehicle caused by the carriageway.
EP 1 305 192 B1 discloses a driver protection system which includes a bow frame which is pivotably mounted with a hinge to a pillar of the vehicle and is held to the other pillar by means of a locking system. That system has proven good in practice in regard to the reliable protection effect which is achieved even in relation to different body sizes, while ensuring adequate freedom of movement for the driver.
It is precisely in relation to fork lift trucks that in addition from time to time there is a need to be able to open the vehicle or driver protection system, even in constricted space situations. Thus for example for taking goods from block warehouses with pallets stacked one beside, one behind and one above the other, a fork lift truck driver can control the vehicle in regions in which the available width substantially only corresponds to the width of a pallet. Similarly constricted space situations can also occur for example when loading and unloading the load platform of a truck.
Constricted space situations also arise during the electric charging operation for electrically operated fork lift trucks as in that case the vehicles are generally placed closely beside each other at the respective charging stations and are connected to charging units which are closely adjacent to each other. As from time to time the vehicle hood has to be temporarily opened during that charging operation to permit charging gases to escape, in which case the driver protection system is then possibly a hindrance, an opening option for the driver protection system may also be desirable in such situations, in constricted space conditions.
For example DE 200 20 521 U1 discloses a safety device for vehicles, in which pivotal movement of protection bows is effected about an axis extending horizontally transversely with respect to the direction of travel or the longitudinal direction of the vehicle, in which case the protection bows in the rest position are disposed approximately vertically and in the safety position they are disposed approximately horizontally.
Such known systems however suffer from the disadvantage that either the protection bow must be kept relatively short in order to avoid hitting against the upper roof member when the protection bow is opened, whereby the region of protection for the driver in the safety position is reduced, or, to permit the pivotal movement, the existing protection bows already project laterally beyond the vehicle contour in the safety position and thus precisely in constricted space situations can be damaged by the driver or even removed.